Light-emitting diodes (LEDs) are widely used as light sources in semiconductor devices. Compared to conventional incandescent light lamps or fluorescent light tubes, light-emitting diodes have advantages such as lower power consumption and longer lifetime, and therefore they gradually replace the conventional light sources and are applied to various fields such as traffic lights, back light modules, street lighting, and medical equipment.
As the demand for the brightness of light-emitting diodes is getting higher as the applications and developments evolve, it is a common goal for LED industry to make efforts to increase luminescence efficiency and brightness.
FIG. 9 shows a conventional LED package 30 comprising an encapsulation 31; a semiconductor LED chip 32 encapsulated in the encapsulation 31, wherein the semiconductor LED chip 32 comprises a p-n junction 33, and the encapsulation 31 is usually made of thermosetting material, such as epoxy, or thermoplastic material.
The semiconductor LED chip 32 is connected to two conductive frames 35, 36 by a wire 34. The epoxy-encapsulated LED can only work in a low temperature environment since degradation of epoxy can occur at high temperature. Besides, epoxy has high thermal resistance, providing the semiconductor LED chip 32, as shown in FIG. 9, a high resistance to heat dissipation, and thus the conventional LED package 300 is limited to work at low power levels.